Electric power devices with automatically established input voltage connection configuration

ABSTRACT

Electric power devices and control methods are provided which automatically select a line voltage or phase voltage of an AC voltage supply. The electric power device includes a switchable circuit, a sensor and a switch control. The switchable circuit connects to the AC voltage supply, and includes multiple switchable elements. The sensor ascertains a voltage level of the AC voltage supply, and the switch control automatically establishes a configuration of the switchable circuit through control of the multiple switchable elements. The switch control couples the electric power device in a line-line (delta) configuration to the AC voltage supply when the voltage level is in a first voltage range, and a line-neutral (wye) configuration when the voltage level is in a second voltage range.

BACKGROUND

The utility power specifications for different countries and/or regionsof the world can vary. For instance, supplied power in the U.S., Japan,and other countries typically falls within a low-voltage range of, forinstance, 200-208 V, and supplied power in Europe, as well as certainother regions of the world, often falls within a high-voltage range of380-415 V. Thus, computers, servers, data centers, etc., in differentcountries or regions of the world may have different source voltages,and therefore may need to be configured differently for the particularcountry or region within which they are used. This increases complexityof product manufacture and distribution, as well as requires that anappropriate electric power device be used in the appropriate location.Should a change occur, for instance, should a computer or data center berelocated, then the utility power specification at the new location mayrequire a change to the electric power device. For instance, differentelectric power devices may be manufactured for use in differentgeographic locations in view of the different utility powerspecifications of the locations, and it may be necessary to purchase orsubstitute a new electric power device (e.g., converter) to comply witha new utility power specification as a result of a product relocation.

SUMMARY

The shortcomings of the prior art are overcome and additional advantagesare provided through the provision, in one aspect, of an electric powerdevice which includes a circuit, a sensor, and a switch control. Thecircuit is to connect to an AC voltage supply, and includes multipleswitchable elements. The sensor is to ascertain a voltage level of theAC voltage supply, and the switch control is to automatically establisha configuration of the circuit based on the voltage level of the ACvoltage supply, the switch control coupling the electric power device ina line-line (delta) configuration to the AC voltage supply when thevoltage level is in a first voltage range, and a line-neutral (wye)configuration when the voltage level is in a second voltage range.

Advantageously, in one or more aspects, the electric power device,control method and computer program product provided herein incorporatea coupling connection facility which automatically establishes an inputvoltage coupling configuration. In particular, by initially ascertainingan input voltage level of an AC voltage supply, the switch controlautomatically establishes a configuration of the circuit based on thevoltage level of the AC voltage supply to connect the electric powerdevice in a line-line (delta) configuration to the AC voltage supplywhen the voltage level is in a first voltage range, or a line-neutral(wye) configuration when the voltage level is in a second voltage range.In one or more embodiments, the electric power device may include areconfigurable bridge rectifier which includes the circuit, and in oneor more other embodiments, the electric power device may be or include apower distribution unit. Advantageously, the automatic couplingconfiguration facility disclosed enables the use of a common, low-cost200-240 V boost topology power supply. Further, the electric powerdevices disclosed may be employed worldwide, without external jumpers,switches, etc., to customize the connection of the device to the localvoltage supply.

Few additional components are required to implement the automaticconnection configuration facility, with the additional components orchanges being small and at a low cost. Very little additional power lossis added by the facility disclosed herein. In one or more aspects, theautomatic coupling configuration facility is particularly beneficial forIT equipment in the 3-5 kW or above range. Further, when implemented asa three-phase power supply, balanced three-phase power is obtained,which provides better line cord utilization. Further, the risk ofhardware damage due to input overvoltage, such as using the wrongelectric power device in the wrong country or region of the world, iseliminated.

In one or more implementations, the electric power device may furtherinclude a reconfigurable bridge rectifier to connect to the AC voltagesupply, with the reconfigurable bridge rectifier including the circuit.In one or more embodiments, the multiple switchable elements of thecircuit may include multiple silicon-controlled rectifiers, and theswitch control may automatically enable or disable one or moresilicon-controlled rectifiers of the multiple silicon-controlledrectifiers to couple the electric power device in the line-line (delta)configuration or the line-neutral (wye) configuration, dependent on thevoltage level of the AC voltage supply. More particularly, in one ormore implementations, the reconfigurable bridge rectifier may includemultiple diodes connected in-series, with one phase input of the ACvoltage supply being connected to the reconfigurable bridge rectifierbetween two diodes of the multiple diodes connected in-series, andwherein at least two silicon-controlled rectifiers of the multiplesilicon-controlled rectifiers may be connected in-series, with anotherphase input of the AC voltage supply being connected to thereconfigurable bridge rectifier between the silicon-controlledrectifiers of the at least two silicon-controlled rectifiers.

In one or more embodiments, the AC voltage supply may include multiplephase lines and a neutral line, and the electric power device may be asingle-phase power supply. In one or more other embodiments, the ACvoltage supply may be a three-phase voltage supply, and the electricpower device may be a three-phase power supply, with each phase of thethree-phase power supply being connectable by the switch control forline-line operation or line-neutral operation.

In one or more embodiments, the electric power device includes athree-phase power distribution unit, where the AC voltage supply is athree-phase voltage supply, and the three-phase power distribution unitincludes multiple outlet connectors which facilitate connecting multiplesingle-phase power supplies to the three-phase power distribution unit.By way of example, the multiple switchable elements of the three-phasepower distribution unit may include multiple triacs gated by the switchcontrol, the multiple triacs being connected between the three-phasevoltage supply and the multiple outlet connectors. As a further example,the multiple switchable elements may include multiple relays activatedby the switch control, with the multiple relays being connected betweenthe three-phase voltage supply and the multiple outlet connectors.

In one or more implementations, the first voltage range is a low-voltagerange, and the second voltage range is a high-voltage range, with thelow-voltage range being a lower voltage range than the high-voltagerange. By way of example, the low-voltage range may be or include200-208 V, and the high-voltage range may be or include 380

-   -   415 V.

Methods and computer program products relating to one or more aspectsare also described and claimed herein.

Additional features and advantages are realized through the techniquesof the present invention. Other embodiments and aspects of the inventionare described in detail herein and are considered a part of the claimedinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more aspects of the present invention are particularly pointedout and distinctly claimed as examples in the claims at the conclusionof the specification. The foregoing and other objects, features, andadvantages of the invention are apparent from the following detaileddescription taken in conjunction with the accompanying drawings inwhich:

FIG. 1A is a schematic of one embodiment of a circuit which includes anAC voltage supply to which multiple power supplies connect in aline-line (or delta) configuration;

FIG. 1B is a schematic of one embodiment of a circuit which includes anAC voltage supply to which multiple power supplies connect in aline-neutral (or wye) configuration;

FIG. 2 is a cross-sectional elevational view of one embodiment of anelectronics or IT rack which may include one or more electric powerdevices, in accordance with one or more aspects of the presentinvention;

FIG. 3 depicts one embodiment of a single-phase power supply with abridge rectifier coupling the single-phase power supply to an AC voltagesupply, and which is to be modified in accordance with one or moreaspects of the present invention;

FIG. 4 depicts one embodiment of an electric power device to connect toan AC voltage supply, and which is configured as a single-phase powersupply unit, in accordance with one or more aspects of the presentinvention;

FIG. 5 depicts one embodiment of an electric power device to connect toa three-phase AC voltage supply, and which is configured as athree-phase power supply unit, in accordance with one or more aspects ofthe present invention;

FIG. 6 is a schematic illustrating one embodiment of an electric powerdevice configured as a power distribution unit, which is to connect to athree-phase AC voltage supply, and which illustrates (by way of example)the use of different types of switchable circuits, in accordance withone or more aspects of the present invention; and

FIG. 7 depicts one embodiment of a computing system which may implementone or more of the sensing and control aspects of an electric powerdevice, in accordance with one or more aspects of the present invention.

DETAILED DESCRIPTION

Electric power devices, such as AC/DC power supplies and powerdistribution units (PDUs), need to operate based on available worldwidevoltage ranges. Countries or regions of the world may generally begrouped into two line voltage ranges, with some countries falling withina low-voltage range of, for instance, 200-208 V, and others in ahigh-voltage range of, for instance, 380-415 V. By comparison, mostpower supplies, such as, for computers, servers, data centers, etc.,utilize an input voltage supply in the range of 200-240 V. With an ACline voltage or input voltage in the low-voltage range, the electricpower devices may connect in line-line (delta) configuration to drawline voltages from the supply, such as depicted in FIG. 1A.

In particular, FIG. 1A illustrates one embodiment of an electric powercircuit 100 with an input supply or AC voltage supply 101 having a linevoltage in the low-voltage range of 200-208 V, and showing threeseparate power supplies 102 connected in line-line configuration, withone power supply being fed by a connection across lines A-B, anotheracross lines B-C, and a third across lines A-C, as illustrated. Thethree-phase, line-line (delta) wire configuration depicted in FIG. 1Amay typically be provided by building wiring for single-phase systems.However, power products above 3-5 kW are typically three-phase systems,and the product itself needs to provide the correct line-line (orline-neutral (wye)) input to the supplies.

FIG. 1B depicts one embodiment of an electric power circuit 100′connected for a high-voltage range country, where the power supplies 102are connected to the input supply 101′ in line-neutral (wye)configuration. In this configuration, each power supply 102 of theelectric power circuit 100′ is connected across one of line A-neutral,line B-neutral, or line C-neutral, with the resultant phase voltagebeing equal to the line voltage (i.e., the line-line voltage) divided bythe square root of 3, and so the power supply 102 input would be in therange of 220-240 V, that is, assuming a line voltage in the 380-415range. Again, for power distribution components, devices in the range of3-5 kW or less may employ single-phase power, and building wiring mayprovide the correct AC line voltage. For systems in the 3-5 kW range orlarger, a three-phase voltage supply may be used, and either a line-line(delta) configuration or line-neutral (wye) configuration would berequired for connecting the electric power device to the supply.

As one application, the electric power device may be a power supply foran IT or electronics rack of, for instance, a data center. In anotherembodiment, the electric power device may be or include a powerdistribution unit of, for instance, an IT or electronics rack of a datacenter, and which may supply one or more power supplies withinindividual computers, subsystems, servers, drawers, blades, etc., of therack. One embodiment of an electronics rack, generally denoted 200, isdepicted in FIG. 2 by way of example.

In the embodiment shown, electronics rack 200 includes a plurality ofelectronics subsystems 201, which (in one embodiment) may be air-cooledby cool air 202 ingressing via louvered air inlet door 210, andexhausting out louvered air outlet door 211 as hot air 203. Electronicsrack 200 also includes at least one bulk power assembly 204, which mayinclude one or more power distribution units such as disclosed herein.One or more electronic subsystems 201 include, in one example, one ormore processors, associated memory, input/output adapters, disk storagedevices, and (in one or more embodiments) power supplies. Alsoillustrated in FIG. 2, the rack may include an I/O and disk expansionsubsystem 205, which may have, in one detailed example, PCIe card slotsand disk drivers for one or more electronic subsystems of theelectronics rack.

In this rack example, a three-phase AC source feeds power via an ACpower or line cord 206 to bulk power assembly 204, which may divide thesupplied AC power at an appropriate power level for output viadistribution cables 207 to the plurality of electronics subsystems 201.AC power cord 206 may supply, in one example, three phases forinternational 415 V_(RMS), and may have a current limit rating of, forexample, 100 amps. The number of electronic subsystems 201 installed inthe electronics rack is variable and depends on customer needs.

One common solution for electronics racks to be operated in differentparts of the world is to source two different power supplies and/or twodifferent power distribution units (PDUs). As an example, with thissolution, a power distribution unit would typically be factoryconfigured or selected for the appropriate system supply voltagedependent on geography. Moving a system to a different geographiclocation supplied by a different supply voltage (in the other of thelow-voltage range or high-voltage range) may be difficult. With thisapproach, costs increase due to the increased number of device parts,each with reduced volumes. Damage can occur if the wrong PDU is used inassociation with the currently available input voltage range.

Another solution would be to manually superimpose switches or jumpers onthe power distribution unit. Unfortunately, such an approach couldresult in a misconfiguration, again resulting in damage to the device.

A further approach would be to employ wide-range (200-415 V) powersupplies which always operate line-line (delta). The Vienna rectifier isa three-phase supply that can support this input range. Threesingle-phase rectifiers could also be used. The buck+ boost and certainboost regulators can support this input range. The disadvantage to thissolution is that larger-sized devices are required, resulting in adecreased efficiency, additional complexity, and increased costs.

In view of the above, disclosed herein (in one or more aspects) is anelectric power device and method for automatically establishing anelectric power device's coupling configuration to the AC voltage supplyas required based on, for instance, a sensed input voltage, such as aline voltage of the AC voltage supply. By way of example, in one or moreembodiments, the electric power device may be a power supply, and theautomatically configuring may be performed in association with a bridgerectifier of the power supply. The bridge rectifier may be automaticallyconfigured for line-line or line-neutral operation, as required based onthe sensed input voltage. For instance, the power supply may operatefrom a line-line (delta) configuration for a low-voltage range inputvoltage, and a line-neutral (wye) configuration for a high-voltage rangeinput voltage. Advantageously, the solution disclosed herein enables theuse of common, low-cost, 200-240 V boost topology supplies. A singleworldwide part number is achieved, without the use of any externaljumpers, switches, etc. Also, few additional components are added, sothere is little effect on the total size or cost of the power device. Inaddition, any power losses due to the added circuitry are advantageouslyminor.

Generally stated, disclosed herein are electric power devices, methods,and computer program products, which facilitate automaticallyestablishing a configuration of a switchable circuit to couple theelectric power device to an AC voltage supply. For instance, an electricpower device is provided which includes a switchable circuit, a sensor,and a switch control. The switchable circuit is to connect to the ACvoltage supply, and includes multiple switchable elements. The sensor isto ascertain a voltage level of the AC voltage supply, and the switchcontrol automatically establishes a configuration of the switchablecircuit based on the voltage level of the AC voltage supply. The switchcontrol couples the electric power device in a line-line (delta)configuration to the AC voltage supply when the voltage level is in afirst voltage range, and a line-neutral (wye) configuration to the ACvoltage supply when the voltage level is in a second voltage range.

In one or more embodiments, the electric power device includes areconfigurable bridge rectifier to connect to the AC voltage supply. Thereconfigurable bridge rectifier includes the switchable circuit. By wayof example, the multiple switchable elements of the switchable circuitmay include multiple silicon-controlled rectifiers. In such a case, theswitch control automatically enables or disables one or moresilicon-controlled rectifiers of the multiple silicon-controlledrectifiers to couple the electric power device in the line-line (delta)configuration or the line-neutral (wye) configuration, dependent on thevoltage level of the AC voltage supply.

In one or more embodiments, the reconfigurable bridge rectifier mayinclude multiple diodes connected in-series, with one phase input of theAC voltage supply being connected to the reconfigurable bridge rectifierbetween two diodes of the multiple diodes connected in-series, and atleast two silicon-controlled rectifiers of the multiplesilicon-controlled rectifiers may be connected in-series, with anotherphase input of the AC voltage supply being connected to thereconfigurable bridge rectifier between silicon-controlled rectifiers ofthe at least two silicon-controlled rectifiers.

By way of example, the AC voltage supply may include multiple phaselines, and a neutral line, and the electric power device may be asingle-phase power supply. In one or more other embodiments, the ACvoltage supply may be a three-phase voltage supply, and the electricpower device may be a three-phase power supply. In such cases, eachphase of the three-phase power supply is connectable line-line orline-neutral by the switch control controlling the multiple switchableelements.

In one or more embodiments, the electric power device is a three-phasepower distribution unit, the AC voltage supply is a three-phase voltagesupply, and the three-phase power distribution unit includes multipleoutlets, or outlet connectors, which facilitate connecting multiplesingle-phase power supplies to the three-phase power distribution unit.

In one or more embodiments, the multiple switchable elements may includemultiple triacs gated by the switch control. The multiple triacs may beconnected between the input, three-phase voltage supply and the multipleoutlet connectors. In one or more other embodiments, the multipleswitchable elements may include multiple relays activated by the switchcontrol. The multiple relays may be connected between the input,three-phase voltage supply and the multiple outlet connectors.

By way of example, the first voltage range may be a low-voltage range,and the second voltage range may be a high-voltage range, with thelow-voltage range being lower than the high-voltage range. For instance,the low-voltage range may be, or may include, 200-208 V, and thehigh-voltage range may be, or may include, 380-415 V.

As a reference, FIG. 3 depicts one embodiment of a typical power supply300 which includes connections 301 to an AC voltage supply whichincludes a phase_A connection, and a phase_B or a neutral connection,dependent on the implementation. In addition to single-phase powersupply circuitry 302, power supply 300 includes a bridge rectifier 310,which includes (in the depicted embodiment) four diodes 311 in a bridgecircuit configuration to provide the same output polarity for eitherinput polarity voltage signal, to facilitate converting an alternatingcurrent (AC) input to a direct current (DC) output.

In comparison, FIG. 4 depicts one embodiment of an electrical powerdevice 400 configured as a single-phase power supply, in accordance withone or more aspects of the present invention. In this embodiment, threeconnections or wires 401, including phase_A, phase_B, and neutral of theAC voltage supply, are connected to the electric power device 400. Inaddition to single-phase power supply circuitry 402, electric powerdevice 400 includes a reconfigurable bridge rectifier 410, as well as avoltage sensor and switch control 404. As illustrated, along withmultiple series-connected diodes 411, the reconfigurable bridgerectifier 410 includes multiple silicon-controlled rectifiers 412, 412′,configured as two different sub-circuits, one switched in for aline-line (delta) configuration connection, and the other switched infor a line-neutral (wye) connection configuration.

As explained, in one or more embodiments, a voltage level of the ACvoltage supply on lines 401 is sensed to determine whether the voltagelevel is within a first voltage range or a second voltage range. In oneor more embodiments, the voltage level sensed may be a line voltage ofthe AC voltage supply. Dependent on the sensed voltage level, the switchcontrol 404 gates the silicon-controlled rectifiers 412, 412′ to fire asappropriate to configure the power supply for either line-line operationor line-neutral operation. As noted, in one or more embodiments,line-line operation may be employed for a low-voltage range inputsupply, for instance, in the range of 200-208 V, and line-neutraloperation may be employed for a high-voltage range input, for instance,in the range of 380-415 V.

Another embodiment of an electric power device 500 (in accordance withone or more aspects of the present invention) is depicted in FIG. 5,where the electric power device is, by way of example, a three-phasepower supply which repeats in each of the phases the circuitry 405 ofthe single-phase power supply of FIG. 4. In this example, thethree-phase power supply 500 is coupled to a three-phase voltage supply501, which includes phase_A, phase_B, phase_C, and neutral. In theembodiment depicted, each circuitry 405 is connected to be configurableusing a different line voltage and the neutral connection, with onecircuit 405 being connected to phase_A, phase_B, and neutral, anotherconnected to phase_B, phase_C, and neutral, and further connected tophase_C, phase_A, and neutral, as shown. The phases wired to theconverters or bridge rectifiers are staggered to provide equal currenton each phase. In this embodiment, each single-phase bridge rectifier410 (or converter) may be configured with silicon-controlled rectifiers412, 412′ controlled by voltage sensor and switch control 404, asdescribed above in connection with FIG. 4. The output of each circuitry405 may be to a common output voltage bus 510.

By way of further example, FIG. 6 depicts an additional embodiment of anelectric power device 600, in accordance with one or more aspects of thepresent invention. In this embodiment, electric power device 600 isconfigured as a power distribution unit, such as might be used for anelectronics or IT rack of a data center. As in the electric power deviceembodiment of FIG. 5, phase_A, phase_B, phase_C, and neutral connections601 of or to a three-phase voltage supply are provided, and each phaseis shown to include multiple outlet connectors for single-phase powersupply 602. In the example shown, each phase has four outlet connectors,for a total of twelve outlet connectors being provided by the powerdistribution unit to supply, for instance, twelve distinct, single-phasepower supplies 603, which may be located remote to the powerdistribution unit (for instance, within individual subsystems of theelectronics or IT rack). Any number of connectors may be provided by thepower distribution unit. In another embodiment, three connectors perphase may be provided, for a total of nine outlet connectors poweringnine distinct power supply units 603.

The electric power device 600 further includes a voltage sensor andswitch control 604 to sense an input voltage level of the AC voltagesupply, such as a line voltage, as well as to provide operation of thepower distribution unit in either a line-line configuration orline-neutral configuration.

By way of example, connectors for single-phase power supply 602 in onephase of the power distribution unit are shown connected to phase_A, andselectively coupled to either phase_B or neutral, dependent upon whetherline-line or line-neutral operation is desired. In this configuration,multiple discrete triacs 610 may be employed as the switchable elements.Triacs 610 are semiconductor devices which are similar tosilicon-controlled rectifiers, but allow current to flow in bothdirections. In the embodiment depicted, multiple connectors forsingle-phase power supply 602 are connected to another phase, phase_B,as well as selectively connectable to phase_C and the neutral line viatriacs 610′. In this example, the pair of triacs 610′ may be used toswitch in unison all of the outlet connectors for single-phase powersupply 602 in that phase. In such a case, triacs 610′ may be largertriacs than triacs 610 associated with each of the connectors in thephase connected to phase A.

By way further example, in one or more embodiments, relays 611 mayinstead be employed, such as illustrated in the third phase of the powerdistribution unit of FIG. 6. In this configuration, each connector forsingle-phase power supply 602 in this phase is connected to phase_C, andselectively connectable to either phase_A or neutral to allow forline-line or line-neutral operation as described herein.

Note with respect to FIG. 6, that the different switchable elementconfigurations are provided by way of example only. In one or moreembodiments, the same switchable element might be employed in each phaseof the power distribution unit. Note also that the power distributionunit may contain other functions not shown, such as filtering,monitoring, fusing, etc.

From the above description, those of ordinary skill in the art willunderstand that the electric power device disclosed herein may take avariety of configurations, including that of a power supply or a powerdistribution unit. For instance, in one or more embodiments, a powersupply may be provided to operate in either line-line or line-neutraloperation using silicon-controlled rectifiers in the rectifier bridge.In one or more other embodiments, a power distribution unit may beprovided with either line-line or line-neutral outlets, dependent on,for instance, the sensed voltage level of the AC voltage supply providedto the unit.

The aspects disclosed herein are particularly beneficial for ITequipment within or above the 3-5 kW range. The electric power devicesand methods of control disclosed advantageously provide a lower-costsolution to the problem noted. Further, using a three-phase power supplysuch as described with reference to FIG. 5 provides balanced three-phasepower and better line cord utilization. The devices disclosed hereinalso eliminate the risk of hardware damage due to an input overvoltageas a result of a miss-wiring of an electric power device to the suppliedvoltage.

Referring next to FIG. 7, a schematic of an example of a processingsystem 700 is shown, which may be used to implement one or more aspectsof the present invention, such as the voltage sensing and switchcontrol. Processing system 700 is only one example of a suitable systemand is not intended to suggest any limitation as to the scope of use orfunctionality of embodiments of the invention described herein.Regardless, processing system 700 is capable of being implemented and/orperforming any of the functionality set forth herein above, such as thevoltage sensing and switch control functionality discussed.

In processing system 700, there is a computing system 712, which may bedescribed in the general context of computer system executinginstructions, such as program modules. Generally, program modules mayinclude routines, programs, objects, components, logic, data structures,and so on that perform particular tasks or implement particular abstractdata types. One or more aspects of computing system 712 may be practicedin distributed cloud computing environments where tasks are performed byremote processing devices that are linked through a communicationsnetwork. In a distributed cloud computing environment, program modulesmay be located in both local and remote computer system storage mediaincluding memory storage devices.

As shown in FIG. 7, computing system 712 in processing system 700 isshown in the form of a general-purpose computing device. The componentsof detector/computing system 712 may include, but are not limited to,one or more processors or processing units 716, a system memory 723, anda bus 718 that couples various system components including system memory723 to processor(s) 716.

Bus 718 represents one or more of any of several types of busstructures, including a memory bus or memory controller, a peripheralbus, an accelerated graphics port, and a processor or local bus usingany of a variety of bus architectures. By way of example, and notlimitation, such architectures include the Industry StandardArchitecture (ISA), Micro Channel Architecture (MCA), Enhanced ISA(EISA), Video Electronics Standards Association (VESA), and PeripheralComponent Interconnect (PCI).

Computing system 712 may include a variety of computer system readablemedia. Such media may be any available media that is accessible bycomputing system 712, and it includes both volatile and non-volatilemedia, removable and non-removable media.

For instance, system memory 723 can include computer system readablemedia in the form of volatile memory, such as random access memory (RAM)730 and/or cache memory 732. Computing system 712 may further includeother removable/non-removable, volatile/non-volatile computer systemstorage media. By way of example only, storage system 734 can beprovided for reading from and writing to a non-removable, non-volatilemagnetic media (not shown and typically called a “hard drive”). Althoughnot shown, a magnetic disk drive for reading from and writing to aremovable, non-volatile magnetic disk (e.g., a “floppy disk”), and anoptical disk drive for reading from or writing to a removable,non-volatile optical disk such as a CD-ROM, DVD-ROM or other opticalmedia can be provided. In such instances, each can be connected to bus718 by one or more data media interfaces. As will be further depictedand described below, memory 723 may include at least one program producthaving a set (e.g., at least one) of program modules that are configuredto carry out the functions of embodiments of the invention.

Program/utility 740, having a set (at least one) of program modules 742,may be stored in memory 723 by way of example, and not limitation, aswell as an operating system, one or more application programs, otherprogram modules, and program data. Each of the operating system, one ormore application programs, other program modules, and program data orsome combination thereof, may include an implementation of a networkingenvironment. Program modules 742 may generally carry out the functionsand/or methodologies of embodiments of the invention as describedherein.

Alternatively, a separate switch configuration control module, logic,etc., 701 may be provided within computing environment 712.

Computing system 712 may electrically connect to one or more externalcomponents, such as external devices 714 and display 724 via one or moreinterface(s) 722. Also, in one or more implementations, the witchconfiguration control 701 may be provided separately, coupling to theother components of computing system 712 via bus 718, as illustrated inFIG. 7. It should also be understood that although not shown, otherhardware and/or software components could be used in conjunction withdetector/computing system 712. Examples, include, but are not limitedto: microcode, device drivers, redundant processing units, etc.

The control aspects of the present invention may be a system, a method,and/or a computer program product. The computer program product mayinclude a computer readable storage medium (or media) having computerreadable program instructions thereon for causing a processor to carryout aspects of the present invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofaspects of the present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, or either source code or object code written in anycombination of one or more programming languages, including an objectoriented programming language such as Smalltalk, C++ or the like, andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The computerreadable program instructions may execute entirely on the user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).In some embodiments, electronic circuitry including, for example,programmable logic circuitry, field-programmable gate arrays (FPGA), orprogrammable logic arrays (PLA) may execute the computer readableprogram instructions by utilizing state information of the computerreadable program instructions to personalize the electronic circuitry,in order to perform aspects of the present invention.

Certain aspects of the present invention are described herein withreference to flowchart illustrations and/or block diagrams of methods,apparatus (systems), and computer program products according toembodiments of the invention. It will be understood that each block ofthe flowchart illustrations and/or block diagrams, and combinations ofblocks in the flowchart illustrations and/or block diagrams, can beimplemented by computer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprise” (andany form of comprise, such as “comprises” and “comprising”), “have” (andany form of have, such as “has” and “having”), “include” (and any formof include, such as “includes” and “including”), and “contain” (and anyform contain, such as “contains” and “containing”) are open-endedlinking verbs. As a result, a method or device that “comprises”, “has”,“includes” or “contains” one or more steps or elements possesses thoseone or more steps or elements, but is not limited to possessing onlythose one or more steps or elements. Likewise, a step of a method or anelement of a device that “comprises”, “has”, “includes” or “contains”one or more features possesses those one or more features, but is notlimited to possessing only those one or more features. Furthermore, adevice or structure that is configured in a certain way is configured inat least that way, but may also be configured in ways that are notlisted.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements in the claims below, if any, areintended to include any structure, material, or act for performing thefunction in combination with other claimed elements as specificallyclaimed. The description of the present invention has been presented forpurposes of illustration and description, but is not intended to beexhaustive or limited to the invention in the form disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the invention.The embodiment was chosen and described in order to best explain theprinciples of one or more aspects of the invention and the practicalapplication, and to enable others of ordinary skill in the art tounderstand one or more aspects of the invention for various embodimentswith various modifications as are suited to the particular usecontemplated.

What is claimed is:
 1. An electric power device comprising: a circuit toconnect to an AC voltage supply, the circuit comprising multipleswitchable elements; a sensor to ascertain a voltage level of the ACvoltage supply; and a switch control to automatically establish aconfiguration of the circuit based on the voltage level of the ACvoltage supply, the switch control coupling the electric power device ina line-line (delta) configuration to the AC voltage supply when thevoltage level is in a first voltage range, and a line-neutral (wye)configuration when the voltage level is in a second voltage range. 2.The electric power device of claim 1, further comprising areconfigurable bridge rectifier to connect to the AC voltage supply, thereconfigurable bridge rectifier comprising the circuit.
 3. The electricpower device of claim 2, wherein the multiple switchable elements of thecircuit comprise multiple silicon-controlled rectifiers, and the switchcontrol automatically enables or disables one or more silicon-controlledrectifiers of the multiple silicon-controlled rectifiers to couple theelectric power device in the line-line (delta) configuration or theline-neutral (wye) configuration to the AC voltage supply, dependent onthe voltage level of the AC voltage supply.
 4. The electric power deviceof claim 3, wherein the reconfigurable bridge rectifier furthercomprises multiple diodes connected in-series, with one phase input ofthe AC voltage supply being connected to the reconfigurable bridgerectifier between two diodes of the multiple diodes connected in-series,and wherein at least two silicon-controlled rectifiers of the multiplesilicon-controlled rectifiers are connected in-series, with anotherphase input of the AC voltage supply being connected to thereconfigurable bridge rectifier between silicon-controlled rectifiers ofthe at least two silicon-controlled rectifiers.
 5. The electric powerdevice of claim 3, wherein the AC voltage supply comprises multiplephase lines and a neutral line, and the electric power device is asingle-phase power supply.
 6. The electric power device of claim 3,wherein the AC voltage supply is a three-phase voltage supply and theelectric power device is a three-phase power supply, each phase of thethree-phase power supply being connectable by the switch control forline-line operation or line-neutral operation.
 7. The electric powerdevice of claim 1, wherein the electric power device comprises athree-phase power distribution unit, the AC voltage supply is athree-phase voltage supply, and the three-phase power distribution unitcomprises multiple outlet connectors which facilitate connectingmultiple single-phase power supplies to the three-phase powerdistribution unit.
 8. The electric power device of claim 7, wherein themultiple switchable elements comprise multiple triacs gated by theswitch control, the multiple triacs being connected between thethree-phase voltage supply and the multiple outlet connectors.
 9. Theelectric power device of claim 7, wherein multiple switchable elementscomprise multiple relays activated by the switch control, the multiplerelays being connected between the three-phase voltage supply and themultiple outlet connectors.
 10. The electric power device of claim 1,wherein the first voltage range is a low-voltage range, and the secondvoltage range is a high-voltage range, the low-voltage range being alower voltage range than the high-voltage range.
 11. The electric powerdevice of claim 10, wherein the low-voltage range comprises 200-208 V,and the high-voltage range comprises 380-415 V.
 12. A method comprising:providing an electric power device, the providing of the electric powerdevice comprising: providing a circuit to connect to an AC voltagesupply, the circuit comprising multiple switchable elements; providing asensor to ascertain a voltage level of the AC voltage supply; andproviding a switch control to automatically establish a configuration ofthe circuit based on the voltage level of the AC voltage supply, theswitch control to couple the electric power device in an line-line(delta) configuration to the AC voltage supply when the voltage level isin a first voltage range, and a line-neutral (wye) configuration whenthe voltage level is in a second voltage range.
 13. The method of claim12, wherein providing the electric power device further comprisesproviding a reconfigurable bridge rectifier to connect to the AC voltagesupply, the reconfigurable bridge rectifier comprising the circuit,wherein the multiple switchable elements of the circuit comprisemultiple silicon-controlled rectifiers, and the switch controlautomatically enables or disables one or more silicon-controlledrectifiers of the multiple silicon-controlled rectifiers to couple theelectric power device in the line-line (delta) configuration or theline-neutral (wye) configuration to the AC voltage supply, dependent onthe voltage level of the AC voltage supply.
 14. The method of claim 13,wherein the reconfigurable bridge rectifier further comprises multiplediodes connected in-series, with one phase input of the AC voltagesupply being connected to the reconfigurable bridge rectifier betweentwo diodes of the multiple diodes connected in-series, and wherein atleast two silicon-controlled rectifiers of the multiplesilicon-controlled rectifiers are connected in-series, with anotherphase input of the AC voltage supply being connected to thereconfigurable bridge rectifier between silicon-controlled rectifiers ofthe at least two silicon-controlled rectifiers.
 15. The method of claim13, wherein the AC voltage supply comprises multiple phase lines and aneutral line, and the electric power device is a single-phase powersupply.
 16. The method of claim 13, wherein the AC voltage supply is athree-phase voltage supply and the electric power device is athree-phase power supply, each phase of the three-phase power supplybeing connectable by the switch control for line-line operation orline-neutral operation.
 17. The method of claim 12, wherein the electricpower device comprises a three-phase power distribution unit, the ACvoltage supply is a three-phase voltage supply, and the three-phasepower distribution unit further comprises multiple outlet connectorswhich facilitate connecting multiple single-phase power supplies to thethree-phase distribution unit, and wherein the multiple switchableelements comprise multiple triacs gated by the switch control, themultiple triacs being connected between the three-phase voltage supplyand the multiple outlet connectors.
 18. The method of claim 12, whereinthe electric power device comprises a three-phase power distributionunit, the AC voltage supply is a three-phase voltage supply, and thethree-phase power distribution unit further comprises multiple outletconnectors which facilitate connecting multiple single-phase powersupplies to the three-phase power distribution unit, and wherein themultiple switchable elements comprise multiple relays activated by theswitch control, the multiple relays being connected between thethree-phase voltage supply and the multiple outlet connectors.
 19. Acomputer program product for automatically establishing configuration ofa circuit of an electric power device, the circuit to connect to an ACvoltage supply, and the circuit including multiple switchable elements,the computer program product comprising: a computer readable storagemedium having program instructions embodied therewith, the programinstructions being executable by a processing circuit to cause theprocessing circuit to: sense a voltage level of the AC voltage supply;and automatically establish a configuration of the circuit based on thevoltage level of the AC voltage supply, the automatically establishingcomprising automatically coupling the electric power device in aline-line (delta) configuration to the AC voltage supply when thevoltage level is in a first voltage range, and a line-neutral (wye)configuration when the voltage level is in a second voltage range. 20.The computer program product of claim 19, wherein the electric powerdevice comprises a reconfigurable bridge rectifier to connect to the ACvoltage supply, the reconfigurable bridge rectifier including thecircuit, and wherein the multiple switchable elements of the circuitcomprise multiple silicon-controlled rectifiers, and the automaticallyestablish automatically enables or disables one or moresilicon-controlled rectifiers of the multiple silicon-controlledrectifiers to couple the electric power device in the line-line (delta)configuration or the line-neutral (wye) configuration to the AC voltagesupply, dependent on the voltage level of the AC voltage supply.